335 Sessions Measured

The 88% Rule — You Only Need Five Points Out of a 66-Point Day

335 measured SPX sessions. The move almost always happens. Getting there is easy — staying there is the trade.

August 202612 min read
The 88% Rule — a large gold 88% over an SPX intraday chart showing a wide daily range with a narrow five-point band near the close

Quick Answer

What is the 88% Rule in SPX 0DTE trading?

Across 335 measured SPX sessions, the average day travelled 65.9 points high-to-low and every single session travelled at least 5. A $5-wide 0DTE debit spread only needs five points to reach max profit — and with the direction of the day called correctly, it finished at full max profit in 88.1% of those sessions. That 88.1% is a perfect-foresight ceiling, not an expected win rate: it is the best a $5-wide structure could have done, and your real result is that ceiling multiplied by how often you read the day correctly.

The Crowd That Is Already Starving

There is a very specific person reading this. They have a small account. They are not trying to become a hedge fund. They want one clean trade a day, on one instrument, for an amount of money they can name out loud before they click.

Everything sold to that person is built backwards. It is a chat room where nobody tells you what a trade should cost. It is a signal service that fires twelve alerts and never defines the loss. It is a course that teaches Greeks to a person who has never filled an order. It is an indicator pack priced like software and delivered like a hobby.

None of it answers the only two questions that matter to a small account: what does this cost me, and what can it pay me.

I do not sell signals. I sell a reading of the day, priced in dollars, on one index, with a hard ceiling on what any single trade is allowed to cost you.

What I Measured — 335 Sessions

Before anything is sold, something has to be true. So I measured it. Every stored SPX session from 14 April 2025 through 13 August 2026 — 335 trading days. Not a simulation, not a backtest with assumptions bolted on. Observed opens, highs, lows and closes.

65.9

Avg intraday range (pts)

59.0

Median range (pts)

100.0%

Sessions that moved ≥ 5 pts

Here is the full distribution, as measured:

MeasureAverageMedianSessions ≥ 5 pts
Intraday range (high − low)65.9 pts59.0 pts100.0%
Net move (|close − open|)32.8 pts28.5 pts87.5%
Favourable excursion (open → extreme in the eventual closing direction)50.0 pts43.7 pts99.7%

Read the first row again. In every single one of 335 sessions, SPX travelled at least five points between its high and its low. Not most. All of them. The index does not have a movement problem.

Observed from stored SPX session history, 14 Apr 2025 – 13 Aug 2026 (335 sessions). Past behaviour of the index is not a prediction of future behaviour.

The 88% Number (And What It Is Not)

A $5-wide at-the-money debit spread reaches its maximum value when SPX closes just five points beyond your long strike. Five points. Out of a day that averages sixty-six.

So I ran the honest version of the question: across those same 335 sessions, if you had called the direction of the day correctly and bought a $5-wide at-the-money structure at the open, where would it have finished?

Outcome at the closeSessionsRate
Reached full max profit (close beyond the short strike)29588.1%
Partial value (close landed inside the zone)3510.4%
Expired worthless despite the correct direction51.5%

88.1% is a ceiling, not a win rate. It is what a $5-wide structure could have done with perfect foresight — with the direction of the day known in advance. Nobody has that. Your real outcome is that ceiling multiplied by how often you read the day correctly. I publish it as the ceiling because that is what it is, and because a number you can verify is worth more than a number you have to believe.

Everyone in this business sells you a win rate. I am handing you the roof and telling you exactly how much of it you have to earn yourself. That is the whole difference.

Getting There Is Easy. Staying There Is The Trade.

Put two of the measured numbers side by side and the entire strategy falls out of them.

99.7%

Sessions that reached +5 pts in the closing direction

88.1%

Sessions that were still there at the close

The move almost always happens. It does not always stay. That gap — eleven and a half points of percentage — is the entire job.

Every service on the internet claims it can call direction. It is the cheapest claim in trading and the easiest to fake. Direction is not where 0DTE is won or lost, because 0DTE does not settle on the extreme. It settles on the close.

So SPXXL is not built to shout a direction at you. It is built to read whether the day is the kind of day that holds — whether the session is trending and committed, or balanced and rotational, or compressed and about to give everything back into the final hour. That reading is what decides whether you take a directional structure at all, or a structure that gets paid for the day going nowhere.

You Are Asking The Market For Five Points

Four structures. One index. Each one asks the day for something small, and the day averages sixty-six points of travel.

StructureWhat it needs the day to doHow far it has to go
Call spreadFinish higher than where you bought it5 points up
Put spreadFinish lower than where you bought it5 points down
CondorFinish anywhere inside a wide middleStay inside — roughly 65–75 points of room
ButterflyFinish near one specific priceLand on the body — the cheap lottery ticket

You are not asking the market for a miracle. You are asking a sixty-six point day for five points — or, with a Condor, for the day to simply stay inside a sixty-five point room. The width is small. The day is enormous. Everything else is reading which of those two questions today is willing to answer.

And you never have to learn a Greek to do it. Price is the odds. A structure that costs around $400 out of a $500 payout is the market telling you it is roughly an 80% shot. Around $250 is a coin flip. Around $100 is roughly a 20% shot. Around $30 is a 6% lottery ticket that pays $470 if it lands. The price tag is the probability. Read it off the screen.

The Two Numbers That Govern Every Trade

This is the discipline, and it is not negotiable inside the platform:

$400 maximum cost

No trade is ever allowed to cost more than your $400 unit. There is no floor — cheaper is always a better deal. If the confirmation screen shows a max loss above $400, the trade is too expensive. Edit it or delete it.

$100 minimum profit potential

If a structure cannot pay you at least $100, it does not qualify — no matter how safe it looks. A trade that risks real money for pocket change is not a conservative trade. It is a bad one.

Both numbers are printed on your broker's order confirmation screen before you send anything. Max Loss and Max Profit. You do not have to calculate them. You have to read them, and obey them.

Before you hit Send, read Max Loss. If that number is bigger than your unit, the trade is too expensive. If Max Profit is under $100, the trade does not meet the minimum. The confirmation screen does the math for you.

What You Actually Get

Not a chat room. Not an alert firehose. A live reading of the one index that matters, translated into structures with a price on them.

  • Live session classification — the engine reads the SPX session in real time and tells you what kind of day it is, with the confidence decomposed so you can see why.
  • The Close Zone™ projection — where the session is pointing to finish, which is the only price a 0DTE contract cares about.
  • Qualifying structures, priced — Call spreads, Put spreads, Condors and Butterflies, filtered against the $400 ceiling and the $100 minimum, with cost and payout in dollars.
  • Challenge Mode — one qualifying trade a day, enforced by the platform, so the discipline is not left up to your mood at 10:15am.
  • The Backtester and the Track Record — so you can interrogate the engine instead of trusting it.

The Price

One trade at the ceiling costs $400. That is the number this whole platform is built to protect. Price the software against that and it stops being a debate.

PriceWhat it is
Free trial$0 — no credit cardThe full engine for 5 trading days
0DTE 5-Day Pass$39Five trading days of full access, one payment
SPXXL Elite$99 / monthEverything, continuously, cancel any time
SPXXL Elite — annual$899 / yearThe same, at the annual rate

Elite is $99 a month. Your trade ceiling is $400. The platform that governs how you deploy four hundred dollars costs less than a quarter of a single unit — and it is the thing standing between you and a trade that was never allowed to cost that much in the first place.

The Guarantee

Five trading days. The full engine. No credit card.

You are not being asked to believe the 88% number. You are being asked to sit with the engine through a full trading week and watch it read five sessions in front of you — the trending ones, the balanced ones, and the one that gives everything back after 2pm. If at the end of that week it has not changed how you read the day, you walk away. Nothing was charged, because nothing was collected.

I do not need to hold your card hostage to prove a measurement. Five sessions is enough. If it is not, I did not deserve the money.

The Money Model — Getting Paid To Get Customers

Most businesses spend money to find customers and then hope the customers stay long enough to pay it back. That gap is what kills them. I built the terms so the gap does not exist.

  • The free week costs nothing to give. The engine is already running the session for everyone. Letting one more trader watch it read five days costs me nothing incremental — so the offer can stay genuinely free, forever, with no card.
  • The $39 5-Day Pass funds the acquisition. It is a real, paid, self-contained product — not a discount on the subscription. It converts attention into cash on day one instead of on day ninety.
  • Elite at $99/month is the retention. It is priced against a $400 trade unit, not against a $19 indicator, which is why it holds.
  • The affiliate program pays the acquisition out of the revenue it creates. 20% recurring on every payment a referral makes — $39 pass or $99/month subscription — for as long as they stay. Nobody is paid up front out of a marketing budget. They are paid out of money that would not exist without them.

The front end funds the customer. The back end funds the business. The affiliate is paid out of the customer they created. There is no month where growth is limited by how much cash I have on hand to buy attention.

Commission figures describe the affiliate program terms. They are not a projection of any individual's earnings.

Start Reading The Day

Five trading days, free, no credit card. Watch the engine read five sessions and decide for yourself whether the day holds.

No credit card · Cancel any time · $400 maximum cost and $100 minimum profit potential enforced on every trade

All figures on this page are measurements of past SPX session history and current option pricing. They are not predictions and not a guarantee of any result. Options trading involves substantial risk of loss, including the total loss of the amount paid for a position. Nothing here is financial advice.

Frequently Asked Questions

What is the 88% Rule?+
Across 335 measured SPX sessions (14 April 2025 – 13 August 2026), a $5-wide at-the-money 0DTE debit spread closed at full max profit in 88.1% of sessions when the direction of the day was called correctly. It is a perfect-foresight ceiling — the best a $5-wide structure could have done if you knew the direction in advance — not an expected win rate.
Why five points?+
A $5-wide debit spread reaches its maximum value when SPX closes just five points beyond your long strike. The average measured SPX session travelled 65.9 points between its high and its low. You are asking a 66-point day for five of them.
How often does SPX move at least five points in a day?+
In all 335 measured sessions — 100.0% — the intraday range was at least 5 points. The median range was 59.0 points. Movement is not the constraint. Where the day finishes is.
If the move happens 99.7% of the time, why is the ceiling only 88%?+
Because 0DTE settles on the close, not on the extreme. In 99.7% of sessions price travelled at least 5 points in the eventual closing direction at some point during the day. Only 88.1% of sessions actually finished there. Getting there is easy. Staying there is the trade.
What does a trade cost?+
The house rule is a hard ceiling of $400 per trade and a minimum of $100 of profit potential. Cheaper is always better — there is no cost floor. If the confirmation screen shows a max loss above $400 or a max profit under $100, the trade does not qualify.
What does SPXXL cost?+
Start free for 5 trading days with no credit card. After that, a 0DTE 5-Day Pass is $39, and SPXXL Elite is $99/month or $899/year. Cancel any time.
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